The present invention relates to electrical interconnects and, more particularly, relates to the assembly of electrical interconnects incorporating an interposer having resilient wire bundles that provide a conductive path between two electronic substrates. The present invention further particularly relates to apparatus involved in the assembly of such electrical interconnects.
Electrical interconnect devices having resilient wire bundles for providing a conductive path between two electronic substrates are well known to those skilled in the art. Such resilient wire bundles are also known as fuzz buttons, button contacts, button wads or contact wads and shall be collectively referred to hereafter as resilient wire bundles.
One such device is the electrical interconnect device shown in Hopfer, III et al., the disclosure of which is incorporated by reference herein. There, it can be seen that resilient wire bundles are held in a carrier. In use, the carrier is placed between two circuit boards and the resilient wire bundles provide the conductive path between the two circuit boards, As noted in Hopfer, III et al., the resilient bundles wire (contact wads) are held in place in the carrier in their corresponding holes by compressive radial frictional engagement with the side walls of each of the holes.
Metreaud et al. IBM Technical Disclosure Bulletin, vol. 20, no. 7, p. 2695 (December 1977) discloses another use of a resilient wire bundle (fuzz button) in which a depression is formed in the resilient wire bundle to accommodate a chip. The compressed portion of the resilient wire bundle enhances the thermal conductivity of the resilient wire bundle for better cooling of the chip.
Leahy et al. U.S. Pat. No. 5,359,488, the disclosure of which is incorporated by reference herein, discloses another use of a resilient wire bundle (fuzz button) which interconnects a radio frequency package to a ceramic motherboard.
The inherent difficulty with such interconnect devices that use a resilient wire bundle for a conductive path is that the resilient wire bundle is frequently jarred loose from the carrier during transit or handling such that when the interconnect device is placed between two electronic substrates, an open results due to the missing resilient wire bundle. This unfortunate circumstance occurs notwithstanding the teachings of Hopfer, III et al. that the resilient wire bundles are force fitted into the holes in the carrier. When such an open occurs, the interconnect device has to be replaced at some additional cost. Instead of being jarred loose from the carrier, the resilient wire bundle instead could be partially jarred from the carrier such that when the resilient wire bundle is compressed between the two electronic substrates, the resilient wire bundle bends over and makes contact with an adjacent resilient wire bundle causing a short circuit which can result in damage to one of both of the electronic substrates being interconnected. In this latter situation as well, the resilient wire bundle, and possibly also one or both of the electronic substrates being interconnected, would have to be replaced at some additional cost.
In order to remedy the shortcomings of the prior art, it is a purpose of the present invention to have a method of assembling the interconnect device in which the resilient wire bundles are prevented from being jarred loose during handling and transit of the interconnect device.
It is a further purpose of the present invention to have an apparatus for assembling an interconnect device in which the resilient wire bundles are prevented from being jarred loose during handling and transit of the interconnect device.
These and other purposes of the present invention will become more apparent after referring to the following description of the invention considered in conjunction with the accompanying drawings.